The present invention relates generally to driving axles, and more particularly concerns a system for attaching an inboard constant velocity (CV) joint of a driving axle to its mating component so as to facilitate assembly of the driving axle while maintaining torque transmission, concentricity, and serviceability.
It is well known that speed variation problems can be solved by using two universal joints in series. If the joints are properly arranged, the irregularity introduced by one joint will be cancelled out by the equal and opposite irregularity introduced by the second joint. Constant velocity joints include such double universal joints as well as any joint in which the speeds of the shafts connected by the joint are absolutely equal at every instant throughout each revolution. Characteristically, a constant velocity joint includes a shaft with a universal-type coupling at each end. This arrangement is sometimes referred to as a constant velocity shaft
Driving axles are widely used in the automotive industry. Typically, driving axles employ inboard CV joints, an interconnecting shaft, and an outboard CV joint in order to transmit torque from a final drive unit to the driving wheels. These CV joints are used to transmit torque at varying angles caused by vertical movement of the wheels and engine movement resulting from torque reaction. In a front wheel drive vehicle, constant velocity driveshafts are used in pairs. One shaft is located on the left (driver) side of the vehicle and the other is placed on the right (passenger) side. Each shaft has an inboard or plunge coupling that connects the constant velocity shaft to the engine/transaxle and an outboard or fixed coupling that connects the shaft to a left or right wheel. The inboard and outboard couplings and shaft together comprise a constant velocity joint or driveshaft which couples the engine/transaxle shaft to the wheel shaft. In operation, the outboard coupling turns with the wheel around a xe2x80x9cfixedxe2x80x9d center, while the inboard coupling xe2x80x9ctelescopesxe2x80x9d or plunges and turns at an angle sufficient to allow required movement of the automobile suspension system.
Constant velocity joints are also currently used in the drive trains of automotive vehicles. In such vehicles, one universal joint connects a propeller shaft to a rotary output of the transmission while a second universal joint connects the propeller shaft to a wheel. As the vehicle travels over an uneven surface or leans to one side or the other during turns, the wheels move up and down in a plane, approximately normal to the propeller shaft. Therefore, provisions are made in such joints to accommodate for the changes in the distance between the wheel and the transmission as the wheel moves up and down or the engine or transmission vibrates under high loads.
Currently there are three primary systems for attaching an inboard CV joint to its mating component. The first system involves plugging a CV joint into a mating component by aligning splines and sliding the splines together. The connection is secured by a standard circlip. The second system is similar to the first system with the exception that the mating component is plugged into the CV joint. The third system is also similar to the first and second systems except that the CV joint is bolted to the mating component rather than secured by a circlip.
Usually, on a CV joint, a rubberized boot extends axially from the open end of the housing and projects over the driveshaft. Grease is retained within the boot, and lubricates the connection between the driveshaft and the constant velocity joint. The connection is subjected to diverse stresses and strains, and effective lubrication is essential to the proper functioning of the constant velocity joint. The boot, because of its exposed location on an automobile, may be punctured, may be attacked by climatic and road conditions, or may simply wear out after extended use. At such time, as a minimum, the boot must be replaced, and, in many instances, the joint must be repaired. In order to effectuate the necessary replacement and/or repair, the driveshaft and the constant velocity joint must be disassembled.
The current systems for assembling CV joints and mating components are relatively inefficient because time is wasted aligning and securing CV joints and mating components. Also, current systems for disassembling CV joints and mating components are inefficient because often CV joints are not designed for disassembly and, resultantly, many CV joints must be destroyed during separation.
The disadvantages associated with these conventional CV joint assembly and disassembly techniques have made it apparent that a new system for CV joint construction is needed. This new system should have a guiding system to facilitate alignment of the joint and the mating component. Design of this new system should also involve creating CV joints that are easily disassembled from their respective mating components.
It is an object of the present invention to provide an improved attachment system. It is also an object of the present invention to provide an improved attachment system for applications, which include inboard constant velocity joints.
In accordance with the present invention, an attachment system, which couples an inboard constant velocity joint to a mating component, is disclosed. The system includes a stub shaft having an end portion and a first connector integrally formed with the end portion. The first connector includes a polygon-shaped cross-section and a first groove formed therein. A circlip is located in the first groove at the first connector. The system further includes a second connector, which engages the first connector and includes a sleeve which is sized to receive the first connector. The second connector is integrally formed within the mating component. The second connector also has a second groove formed therein which receives the circlip.
Additional objects and features of the present invention will become apparent upon review of the drawings and accompanying detailed description of the preferred embodiments.